I picked up an Orange Pi Zero recently. It’s an interesting Single Board Computer (SBC) with a quad core Allwinner H2.
You can see the full specs here: http://www.orangepi.org/orangepizero/
I found a very nice pinout diagram on the Orange Pi forums:
The best part is that this is a $7 system. $3 for shipping.
It has 26 pins for GPIO, 9 of which are Ground and 3.3/5v power. That leaves 17 for fun and games.
It also has a dedicated audio in/out, USB header, IR in, and TV out. All bundled to a quad core 1080P chip with wired and wireless ethernet.
It still needs a microSD card, but an 8GB unit can be had for $3.50 from AliExpress. You also need a micro-usb power source. no big deal.
The OS can be downloaded from Armbian.org here https://www.armbian.com/orange-pi-zero/
default user/pass root/1234
The Armbian image is based on Debian Jessie and needs about 1.2G of storage.
I was unable to get the video out to work, but I think it’s a driver issue.